* Implement gomatrixserverlib.HeaderedEvent, which should allow us to store room version headers along with the event across API boundaries and consumers/producers, and intercept unmarshalling to get the event structure right
* Add federationsender to previous
A conditional is added to wrap the call to appserviceAPI if a local alias is not found in the database.
Fixes#631
Signed-off-by: Serra Allgood <serra@allgood.dev>
